Ports are facing several logistical challenges and changes in globalization patterns. For this reason, port operations need to be more efficient than ever. Moreover, they can be classified as maritime operations, terminal operations, and connectivity or land operations. Regarding this, maritime operations represent around 48% of the transport costs and are defined as the processes involved from a vessel's arrival to a dock until the end of its cargo transference. This research focuses on the efficiency analysis of these operations using data envelopment analysis and proposes a method for estimating economic impacts when efficient maritime operations are achieved. A literature review is carried out in order to present a classification of port variables used in data envelopment analysis. In this way, the variables' classification supports the selection of maritime operation variables for the efficiency analysis. A case study of twelve Chilean containerized port cargo terminals is used to illustrate the proposed method, where results of the analysis are discussed. For inefficient ports, medium and long-term recommendations (goals) are presented and economic savings are estimated. In this way, the proposed methodological framework can be a useful tool to support policy-making decisions with respect to prioritizing port infrastructure investments.